Indian tennis star Sania Mirza and her Zimbabwean partner Cara Black clinched the WTA finals women's doubles title in Singapore on Sunday. The Indo-Zimbabwean pair thrashed the defending champions Peng Shuai of China and Hsieh Su-wei of Chinese Taipei by 6-1, 6-0 in the one-sided final clash to lift the trophy. The winning pair received $5 lakh in prize money.